<template>
  <view>
    <!-- 使用自定义的搜索组件 -->
    <!-- <my-search :bgcolor="'pink'" :radius="3"></my-search> -->
    <my-search @click="gotoSearch"></my-search>
    
    <view class="scroll-view-container">
      <!-- 左侧的滑动区 -->
            <scroll-view class="left-scroll-view" scroll-y="true" :style="{height: wh + 'px'}">
                <block v-for="(item, i) in cateList" :key="i">
                  <view :class="['left-scroll-view-item',i === active ? 'active' : '']" @click="activeChanged(i)">{{item.cat_name}}</view>
                </block>
              </scroll-view>
            <!-- 右侧的滚动视图区域 -->
            <scroll-view class="right-scroll-view" scroll-y="true" :style="{height: wh + 'px'}" :scroll-top="scrollTop">
              <view class="cate-lv2" v-for="(item2, i2) in cateLevel2" :key="i2">
                <!-- 二级分类的标题 -->
                <view class="cate-lv2-title">/ {{item2.cat_name}} /</view>
                <!-- 当前二级分类下的三级分类列表 -->
                <view class="cate-lv3-list">
                  <!-- 三级分类的tem 项 -->
                  <view class="cate-lv3-item" v-for="(item3, i3) in item2.children" :key="i3" @click="gotoGoodsList(item3)">
                    <!-- 图片 -->
                    <image :src="item3.cat_icon"></image>
                    <!-- 文本 -->
                    <text>{{item3.cat_name}}</text>
                  </view>
                </view>
              </view>
            </scroll-view>
    </view>
  </view>
</template>

<script>
  export default {
    data() {
      return {
        //当前设备可用的高度
        wh:0,
        cateList:[],
        active:0,
        //二级分类的列表
        cateLevel2: [],
         scrollTop: 0
      };
    },
    onLoad(){
      const sysInfo = uni.getSystemInfoSync()
      this.wh = sysInfo.windowHeight - 50
      
      this.getCateList()
    },
    methods:{
      //获取分类列表的数据
      async getCateList(){
        const {data: res} = await uni.$http.get('/api/public/v1/categories')
         if (res.meta.status !== 200) return uni.$showMsg()
          this.cateList = res.message
          
          //为二级分类赋值
          this.cateLevel2 = res.message[0].children
      },
      activeChanged(i){
        this.active = i
        
        //重新为二级分类赋值
         this.cateLevel2 = this.cateList[i].children
         
         this.scrollTop = this.scrollTop === 0 ? 1 : 0
      },
      //跳转到商品列表页面
      gotoGoodsList(item) {
         uni.navigateTo({
            url: '/subpkg/goods_list/goods_list?cid=' + item.cat_id
          })
      },
      gotoSearch(){
        uni.navigateTo({
            url: '/subpkg/search/search'
          })
      }
    }
  }
</script>

<style lang="scss">
.scroll-view-container{
   display: flex;
   
   .left-scroll-view{
     width: 120px;
     
     .left-scroll-view-item{
       background-color: #f7f7f7;
       line-height: 60px;
       text-align: center;
       font-size: 12px;
       
       &.active{
         background-color: #ffffff;
         position: relative;
         
         &::before {
           content: ' ';
           display: block;
           width: 3px;
           height: 30px;
           background-color: #c00000;
           position: absolute;
           left: 0;
           top: 50%;
           transform: translateY(-50%);
         }
       }
     }
   }
}

.cate-lv2-title{
    font-size: 12px;
    font-weight: bold;
    text-align: center;
    padding: 15px 0;
}

.cate-lv3-list {
  display: flex;
  flex-wrap: wrap;

  .cate-lv3-item {
    width: 33.33%;
    margin-bottom: 10px;
    display: flex;
    flex-direction: column;
    align-items: center;

    image {
      width: 60px;
      height: 60px;
    }

    text {
      font-size: 12px;
    }
  }
}
</style>
